LCM for 7 and 28
What's the Least Common Multiple (LCM) of 7 and 28?
(Twenty-eight)
Finding LCM for 7 and 28 using GCF's of these numbers
The first method to find LCM for numbers 7 and 28 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:
LCM = (Number1 × Number2) ÷ GCF
GCF of numbers 7 and 28 is 7, so
LCM = (7 × 28) ÷ 7
LCM = 196 ÷ 7
LCM = 28
Finding LCM for 7 and 28 by Listing Multiples
The second method to find LCM for numbers 7 and 28 is to list out the common multiples for both nubmers and pick the first which matching:
Multiples of 7: 7, 14, 21, 28, 35, 42
Multiples of 28: 28, 56, 84, 112, 140, 168, [...], 28
So the LCM for 7 and 28 is 28
Finding LCM for 7 and 28 by Prime Factorization
Another method to find LCM for numbers 7 and 28 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors:
All Prime Factors of 7: 7 (exponent form: 71)
All Prime Factors of 28: 2, 2, 7 (exponent form: 22, 71)
71 × 22 = 28
Related Calculations
See Also
- Greatest Common Factor - Find the Greatest Common Factor (GCF) of two numbers
<a href="https://calculat.io/en/number/least-common-multiple-lcm-of/7--28">What is the LCM of 7 and 28? - Calculatio</a>
LCM Table
About "Least Common Multiple" Calculator
Least Common Multiple (LCM) also known as the Lowest Common Multiple or Smallest Common Multiple of 2 numbers - it is the smallest positive integer that is divisible by both numbers